Trolley section switch



J. F. CUNRAD 2,4955%9 TROLLEY SECTION SWITCH 2 Sheets-Sheet 1 Filed April 21,, 1947.

Inventor mmw Q R m Fame 24% NH J. F. CONRAD TROLLEY SECTION SWITCH '2 Sheets-Sheet 2 Filed April 21,. 1947 Inventor John Francis Conrad atented Jan, 24, 1950 STATES PATENT OFFICE 1 Claim.

This invention relates to an improved section of trolley switch for underground use, especially as used in connection with cars in mines, and more particularly coal mines.

The object of this invention is toprovide a novel construction and arrangement of switch with a rotating motion, and is designed to close or open either right or left hand and which when opened under a load, causes the arcing to take place on the opposite side from the handle, thereby protecting the operator.

Another object of the invention is to provide a switch which will require less than one third the copper required in an ordinary conventional type of switch and in which the operator is considerably less exposed to live parts which make it safer tooperate in addition to being of higher efficiency not only because the current has a much shorter path to travel, but because the blade is under constant spring pressure and the capacity of the blade is greater than the conventional types of switches.

Another outstanding advantage of the switch the fact that it opens and closes parallel with the trolley wire instead of operating at right angles to the wire, thus making it more compact and easier to operate with the operating handle hanging downwardly, instead of extending outwardiy in a horizontal position at right angles to the switch block and saddle with the switch blade disposed horizontally as in conventional switches, the switch blade in the present improved switch swinging vertically on a horizontal axis and lending the device to more simple, durable, rigid and economical construction, repair and replacement of parts.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a side elevation of an improved section trolley switch constructed in accordance with the invention;

Figure 2 is an enlarged vertical sectional view taken on the section line of 22 of Figure 1;

Figure 3 is a top plan view of the structure which is shown in Figure 1;

Figure 4 is a vertical sectional view taken on the line 4-4 of Figure 3;

Figure 5 is a perspective view showing the switch blade;

Figure 6 is a fragmentary sectional view taken on the line 6-6 of Figure 2, and

Figure '7 is a fragmentary sectional view taken on the line 1-4 of Figure 2.

Referring to the drawings in detail, in which like reference characters designate corresponding parts throughout the several views, my improved section trolley switch is shown as comprising an elongated di-electric body shown in the form of an elongated rectangular wood block H) relatively flat and wide in the direction of a vertical dimension and as such, designed primarily for use in connection with 250 to 550 volt D. C. circuit for use underground or otherwise. Secured to and extending from opposite ends horizontally of the block H] as by means of vertical screws I l extending down through the block from the top vertically and in spaced relation longitudinally of the block adjacent each end, are cable connectors or sockets l2 of copper or other current conductive metal having each a top wall H which extends beneath the block at a suitable distance and is provided with threaded sockets M for engagement by the threaded ends of the bolts or screws II and formed with channels or sockets l5 extending longitudinally thereof at the bottom forming channel shaped or tubular portions or sections id for connection with trolley wires 11 extending thereinto from the outwardly tapered ends l8 of the connectors. Clamping or set screws l9 operate through threaded holes 20 in the wall E3 to engage the trolley wire ends and detachably or securely connect the same to the switch at the connectors i2. The connectors i2 at their top walls [3 are formed with vertical lugs or projections 21 forming shoulders abutting the ends of the block ill and provided with sockets 22 longitudinally thereof, for connection with feed cables held in position by binding and clamping screws 23 supplying current to the switch.

Between the inner ends of the connectors l2 and spaced therefrom is a bronzecast center piece 24 forming air gaps 25 at each end thereof and between said ends and the inner ends of the connectors. The center piece 24 is secured in position in connection with a saddle 26, preferably of flanged bronze, channeled to fit over the top edge of the block it and having suitable holes for receiving securing screws or bolts 21 therethrough as well as vertically downwardly through the block in the direction of its height or width and centrally of its thickness ior engagement with apertures or sockets 28 in the top of the center piece 24 to connect the three parts. The connectors I2 form an underrun, in conjunction with the center piece 24, and the connectors or sockets l2 at their inner ends of top walls I 3 are each provided with a lateral horizontal projection or shelf 29- extending outwardly at one side and formed with an integral vertical flange 3B which may be separate from or cast integral with the underrun connectors I2 and disposed against block Ill adjacent but spaced from center piece 24 and inclined over the air gaps 25. Secured against the outer face of each flange 30 detachably as by means of fastening screws 3| is a renewable copper contact plate 32 resting on each shelf or projecting ledge 29 and retained in position thereby. Secured against the outer edge of each projection or shelf 29 as by means of fastening screws 33 is a similar contact plate 34 disposed in spaced parallel relation to the contact plate 32 and designed to co-operate and be connected by a segmental copper contact blade 35 which swings in the space therebetween and engages the same.

Disposed through the depending side flanges 36 of the saddle 25 and through an aligned bore through the wood block I so that the semicircular flanges of the saddle form bearings, is a horizontal shaft 37 on one end of which is fixed a rocker 38 spaced from the flange of the saddle adjacent thereto and provided with a horizontal bottom channel 39 receiving the corresponding truncated upper edge of the segmental blade 35 therein for connection therethrough by suitable fastenings such as rivets ll] to rigidly secure the blade to the rocker. The blade thus takes an arcuate form, especially at its outer or bottom edge, in order to swing between the contacts 32 and 34 on the shaft 31 as a horizontal pivot axis. Thus, the switch has a rotating motion and is designed to close or open right or left hand, so that when the switch is opened under a load, the arcing takes place on one side only or opposite the operating handle of the switch to be later described, thereby protecting the operator. Moreover, the parts are constructed in such a simple manner that less than one-third of the copper required in the conventional type of switch, is necessary. In addition to the fact that the switch opens and closes parallel with the trolley wire instead of at right angles to the wire or horizontally, making the structure more compact and less likely to cause injury to the operator.

These features are made possible by extending the shaft 37, which is preferably of steel, laterally considerable distance beyond the opposite side of the switch and block and thickening the adjacent flange 35 to form a good bearing in connection with a reduced end portion 4| receiving a spring retaining sleeve or tubular shell 42 preferably of suitable insulation, over said reduced portion 4i and the attaching sleeve 43 of an insulating operating handle 4-4 rigidly fixed or pinned to the outer end of the shaft 3'! as indicated at 35, in the same manner as the rocker 38 is fixed or pinned to the opposite end of the shaft 31 and so designated. within the insulating sleeve or tubular shell 32 for a coil spring 46, fitted on the shaft between washers ll at the end thereof, adjacent the reduced portion ll and the sleeve 63, in order to exert sufficient resilient tension to maintain the shaft in frictional projection at one end or urging or distending the same in transitory positionso that the blade 35 will properly engage the contact plates 3-2 and 34 at all times to make a good electrical contact and connection.

This provides a hollow chamber The. handle 44, which may be of wood or other insulat-.

ing or di-electrlc material, is preferably secured to either of two circular projections or bosses 43' on the sleeve 33 by means of a threaded shank engaging threaded bores in the bosses 43', as indicated at 43, with an interposed relatively large and laterally projecting insulating washer or shield 59, so as to protect the operator from coming in contact at his hands, with any of the electrical parts of the switch when operating the same at the switch blade. In this sense, the Washer serves as a flange or guard and stops for the hand.

It is also to be understood that the contact plates 32 and 34 may be formed integral with the connectors and serve as guiding means for the switch blade 35 above or at the center piece, with upwardly and inwardly extending contact arms or plates 32 and 34 on flanges so and projections or shelves 29, having inclined portions or bottom edges 59 extending upwardly from the connectors i2 and secured to or formed integral therewith atone side of each flange 36 against block H] or extending upwardly to a space or center recess therebetween in oppositely inclined positions to conform at their upper inclined edges with the radial ends of the switch blade 35 when in central position, as shown in Figure 1 of the drawings, so as to connect the contacts or plates 32 and 3G and provide a circuit at the switch between the trolley wires connected as described. Of course, a switch blade may be swung to clear either one of the contacts 32 and 34, either right or left, so as to be readily operated with equal facility in either direction and in spaced relation to the block l9 and switch contacts or plates 32 and at either end of blade 35 and at the opposite side of the switch, so that when the switch is opened under a load, the arcing will take place on the opposite side from the handle, thereby protecting the operator. For this purpose, handle id is mounted in either boss 4 3 and flange 38 has spaced outstanding projections or stops 36 cleared by bosses 42 on sleeve 52 having threaded sockets to receive a stop screw 3'1 in either socket to limit turning of the switch in either direction by engaging a stop 36 at one side when handle 54 is reversed in position in bosses 53 for right or left hand operation or throw. Holes are also provided in rocker 33 to receive a padlock to lock the switch and blade 35 open at either side. Thus, the operator is exposed to considerably less live parts making the switch safer to operate and giving the current a much shorter path to travel. However, since the blade is under constant spring pressure of the spring the capacity of the biade may be greater than in the conventional types. It is to be observed that the switch opens and closes by handle operating in. spaced relation to and parallel with the trolley wire, instead of at right angles to the wire, thus leaving the switch relatively fiat and compact and less likely to be accidentally opened or closed since the switch handle extends downwardly and operates on a horizontal axis instead of extending laterally outwardly a considerable distance and operating on a vertical axis as is the usual construction.

In view of the foregoing description taken in conjunction with the accompanying drawings it is believed that a clear understanding of the device will be quite apparent to those skilled in this art. A more detailed description is accordingly deemed unnecessary.

:.It is to be understood, however, that even though there is herein shown and described a,

preferred embodiment of the invention the same is susceptible to certain changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claim.

Having described my invention, what I claim as new is:

A trolley section switch comprising a flat base member, trolley wire sections extending along the bottom of said member and spaced apart with confronting ends, lateral shelves on said sections adjacent the confronting ends thereof and extending from one and the same side of said member, separated pairs of laterally spaced contact plates fixed on said shelves in planes parallel to the median plane of said member, a rock shaft journaled in said member transversely thereof, a handle on one end of said shaft for rocking the 6 same, and a switch blade on the other end of said shaft swingable in opposite directions by oscillation of the shaft to bridge said pairs of contacts in either direction in which the same may be swung.

JOHN FRANCIS CONRAD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,244,720 Englund Oct. 30, 1917 1,285,006 Bolus Nov. 19, 1918 1,629,893 Suppes May 24, 1927 

